| Pronunciation | PEP-tik UL-ser dih-ZEEZ |
| Definition | A sore or hole in the lining of the stomach or the first part of the small intestine, causing burning pain in the gut. Most ulcers are caused by an infection with a type of bacteria called Helicobacter pylori (H. pylori); other causes include long-term use of nonsteroidal anti-inflammatory drugs (such as aspirin and ibuprofen), alcohol, and tobacco. |
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